Method and apparatus for jet bulking of yarn



Nov. 7, 1961 w. WILLIAMS ETAL 3,007,298

METHOD AND APPARATUS FOR JET BULKING 0F YARN Filed May 22, 1956 2 Sheets-Sheet 1 Mil/am Wil/fams Jose M1 A. l/l/y/ae gr Maw M 7% METHOD AND APPARATUS FOR JET BULKING OF YARN Filed May 22, 1956 Nov. 7, 1961 w. WILLIAMS ETAL 2 Sheets-Sheet 2 W////am l/l/il/mms BY Joseph R. VVy/a'e M42 M44 1 M United States Patent Ofi ice 3,007,298 Patented Nov. 7, 1961 3,007,298 METHOD AND APPARATUS FOR JET BULKING F YARN William Williams and Joseph Rowland Wylde, Spondon, near Darby, England, assignors to British Celanese Limited, a corporation of Great Britain Filed May 22, 1956, Ser. No. 586,894 Claims priority, application Great Britain May 31, 1955 4 Claims. (Cl. 57-34) This invention relates to textile materials and their production, and in particular to yarns having a basis of continuous filaments but having in some degree the appearance and properties of spun yarn, that is yarn made from staple fibre.

USA. Patent No. 2,067,251 describes a process and apparatus for collecting con-tinuous filaments in a form suitable for them to be cut or otherwise formed into staple fibres for the production of a staple fibre yarn, in which travelling continuous filaments are blown forward so as to separate them from one another and are wound while they are separated so as to collect them in a state of substantial but incomplete parallelism with one another. U.S.A. patent applications Ser. Nos. 356,349, filed the 21st of May 1953, now Patent No. 2,942,402, and 540,596, filed the 14th of October 1955 each describe a method and apparatus in which a yarn or bundle of substantially parallel continuous filaments is formed into a continuous filament voluminous yarn having loops of individual filaments projecting from the main body of the yarn, by passing the continuous filament bundle through a jet by which it is subjected to the action of a turbulent fluid stream (preferably air) to whip the filaments about and form them individually into loops and convolutions. The filaments are drawn away from the jet at a speed lower than that at which they are supplied to it and the degree of voluminosity and loopiness can be controlled by varying the ratio between the speeds of supply and withdrawal of the material, so as to give a predominant loop 'form varying from a mere waviness of the filament, or arch-like form of greater or less depth, to a form in which the filament returns upon and crosses itself to give a ring-like loop. The filaments drawn oil are twisted together into a continuous filament yarn in which the loops and convolutions formed therein are locked by the twist imparted and prevented from being pulled out.

It has now been found that the ultimate object of U.S.A. Patent No. 2,067,251, namely the production from continuous filaments of a staple fibre yarn, can be achieved directly by modifying the methods and apparatus described in USA. patent applications Ser. Nos. 356,349, filed the 21st of May 1953, now Patent No. 2,942,402, and 540,596, filed the 14th of October 1955. If in these methods thedegree of turbulence is sufliciently increased, and encouraged if necessary by modification of the surfaces with which the filaments are blown into contact, it is found that the filaments can be torn and broken at intervals along their lengths in the course of being whipped about to modify their parallelism and to form them into loops and convolutions. The resulting product instead of being a continuous filament product is a product having the appearance andcharacterist-ics of a staple fibre yarn, including the feature of exhibiting protruding fibre ends on the surface of the yarn.

According to the present invention, therefore, a method of producing from continuous filaments a yarn having the appearance and properties of a staple fibre yarn comprises passing a continuous filament bundle through a turbulent stream of fluid (preferably air) having a degree of turbulence sufiicient to whip about and break the individual filaments at intervals along their lengths, drawing the filaments out of said turbulent stream at a speed lower than that at which they are fed to it, and collecting them as a continuous textile product. As mentioned above, the degree of voluminosity can be controlled by varying the ratio between the speeds of supply and withdrawal of the filaments. The filaments may, as in U.S.A. patent applications Ser. Nos. 356,349, filed the 21st of May 1953, now Patent No. 2,942,402, and 540,596, filed the 14th of October 1955, be directed by the fluid stream against a surface, which is adapted to break up and disperse the fluid stream, and from the neighbourhood of which the filaments are drawn away.

The severing of the individual filaments at intervals along their length may be eifected by merely increasing the supply pressure and velocity of the air stream so as to raise its turbulence to a sufficient degree of violence. Alternatively or in addition, however, a surface or surfaces past which the filaments are drawn in subjecting them to the action of the air stream may be suitably roughened so as to encourage the breakage of the filaments. Thus an apparatus according to the invention for carrying out the method defined above may comprise a jet member having a through passage for a continuous filament bundle, means for supplying fluid under pressure to the interior of said jet member to form a turbulent fluid stream therein, the interior of said jet member being formed with abrasive surfaces adapted to be engaged by the filaments under the influence of said turbulent stream, and means for drawing away and collecting as a textile product the filaments emerging from said jet.

For example, the outlet orifice of the jet may be in the form of an inserted ring of emery, Carborundum or the like, into engagement with which the filaments are directed by the turbulent stream. Or again, where the stream directs the filaments against a deflecting surface outside the jet, a part of this surface with which the filaments make contact may be of an abrasive character, e.g. being faced with emery or Carborundum or being cut in the manner of a file.

The product drawn away from the turbulent stream is preferably collected directly as a finished yarn, being twisted as it is collected (C-g. by means of a ring-spinning or other twisting and winding device) so as to bind in and lock both the loops and convolutions and the free fibre ends formed in it by the action of the turbulent streanr. Alternatively, however, the filament bundle supplied to the fluid stream may be of a weight many times greater than the yarn ultimately required and the prodnot drawn away from the stream may be subjected to drafting operations, with or without intermediate operations for the further severance of the filaments to convert them into staple fibres. In such a case the tension imparted by the drafting operation may in some degree pull out and straighten the loops and convolutions formed in the individual filaments. However, the relatively voluminous character of the product being drafted need not be wholly destroyed by the drafting operation and is in any case advantageous in the drafting operation itself as increasing the degree of uniformity of drafting and the uniform character of the drafted product. Whether or not the product emerging from the stream is subjected to an intermediate operation, eg one of abrasion, for the further severance of the filaments into staple fibres the drafting operation itself may act to reduce any unduly long lengths of fibre existing in the product.

The method according to the present invention is suitable for the treatment of artificial continuous filament yarns in general and particularly to yarns of cellulose derivatives e.g. of cellulose esters such as cellulose acetate and cellulose butyrate, cellulose ethers such as ethyl cellulose and benzyl cellulose. The invention is also applica ble, however, to continuous filament yarns of regenerated cellulose such as viscose and to yarns of synthetic polymers such as polyhexamethylene adiparnide, polyaminocaproic acid, polyaminotriazoles, polyaminonitrile and polyethylene terephthalate.

The continuous filament bundle may be supplied from any suitable source, erg. from bobbins, cones or cheeses or directly from the spinning machine in which the filaments are formed. Preferably, the bundle has little or no twist, e.g. a twist of 1 turn per inch or less. Yarns with a higher degree of twist may, however, be used, the twist having the effect of moderating the degree of voluminosity achieved, but being nevertheless, apparently opened up by the turbulent stream so as to permit the filaments to be whipped about. Where the filament bundle is thus twisted before it is delivered to the fluid stream, e.g. by drawing it from a rapidly rotating package, the resulting product may be collected by merely winding it without twisting. Where a heavy continuous filament bundle is to be employed, to be formed into a staple fibre sliver or roving for subsequent drafting and spinning, a number of continuous filament bundles, drawn from a number of packages or from several spinning heads in a spinning metier, may be assembled into a heavy bundle for presentation to the turbulent stream. Or again, a heavy bundle may be made up of waste continuous filament yarns. These may be residual yarns left on cones, cheeses, pirns and like packages which have been used and nearly exhausted in a textile operation. The

'waste yarn can be stripped from the package by means of an air jet, as described in USA. Patent No. 2,670,154, and the resulting product, instead of being collected at random in a can or like large receiver may be wound up or otherwise collected in a form suitable for use as a tow for conversion into staple fibre. Indeed, by the use of an air jet adapted to subject the filaments to forces which whip them about sufiiciently to form loops and convolutions the waste yarns may be treated in accord ance with the present invention, and converted directly into a product having the appearance and properties of a staple fibre product, in the operation of drawing them from the package on which they exist as waste.

By way of example some forms of apparatus suitable for carrying out the present invention will now be described in greater detail with reference to the accompanying drawings in which:

FIGURE 1 shows one form of apparatus in which the yarn is twisted as it is collected,

FIGURE 2 shows in greater detail the form of air jet employed in FIGURE 1,

FIGURE 3 shows a second form of apparatus in which the :feed and draw-ff rollers are combined as a single unit,

FIGURE 4 is a form of apparatus in which a yarn is twisted before it reaches the air jet,

FIGURE 5 shows a form of apparatus in which the product leaving the air jet is drafted before being collected, and

FIGURES 6 and 7 are diagrammatic sections of two types of yarn produced in accordance with the invention.

The apparatus shown in FIGURE 1 is of the kind described in USA. patent application Ser. No. 356,349 filed the 21st of May 1953, now Patent No. 2,942,402, and comprises a feed roller 7 for drawing a continuous filament yarn 8 over-end from the packages 9 by way of a balloon guide 11. The yarn is passed twice around the feed roller 7, by way of three back-guides 12. From the third back-guide the yarn proceeds directly to an air jet 13 of the kind described in the above-mentioned specification, supplied through its supply pipe 14 with compressed air at a substantial pressure, e.g. from to 60 lbs. per square inch. The yarn 1'5 emerging from the jet 13, is directed against a fiat plate or bafile 16 disposed at an angle of 45 to the axis of the jet 13, and is drawn away from the neighbourhood of the plate 16 by a pair of draw-oil rollers 17 driven at a peripheral speed less than the peripheral speed of the feed roller 7, e.g.

4 by 5 to 50%. The draw-off rollers 17 act as feed rollers delivering the yarn 15 to the balloon guide 18 of a ringspinning unit 19 by means of which the resulting yarn is twisted and wound into a package 21.

The jet 13, as shown in FIGURE 2 comprises a T- member 22 of which the air supply pipe 14 is constituted by the horizontal single arm, connected to the compressed air supply while the double arm 23, 24 is vertical. The yarn 8 enters the jet by an inlet tube 25 adjustably screwed in the upwardly extending arm 23 of the T and having an internal diameter which is somewhat greater than that of the yarn 8 and is uniform except that the entrance to the tube 25 is flared at 26 for ease in threading up. The yarn 15 leaves the jet 13 by means of an outlet nozzle 27 at the bottom of the downward arm 24 of the T, the aperture 28 of the outlet nozzle being slightly offset from the axis of the inlet tube 25. The compressed air entering the chamber 29 constituted by the vertical arms 23, 24 of the T forms a turbulent stream which whips the filaments 8 about in the space between the lower end of the inlet tube 25 and the outlet nozzle 27. Thereby, it not only separates the filaments 8 and forms them individually into loops, whorls and convolutions but also causes them to be individually torn and broken at random intervals along their length. The reduced speed at which the yarn 15 is drawn away by the draw'ofi rollers 17 ensures that the loops, whorls and convolutions are not pulled out of the yarn 15 before they are fixed therein by the twist imparted to the ring-spinning unit 19.

If desired the breaking and tearing action of the turbulent air stream can be augmented and encouraged by the provision of rough surfaces against which the filaments 8 are caused to engage while being whipped about to form them into loops and convolutions. Thus, the outlet nozzle 27 of the air jet 13 may be provided with an annulus 31 of abrasive material surrounding the outlet aperture 28.

In the form of apparatus shown in FIGURE 3 the feed and draw-off rollers are combined as a single unit. The unit comprises a supply roller 32 for a ring-twisting device (not shown), a compound roller 33 resting thereon and having two portions 34, 35 of different diameters and a presser roller 36 surfaced with cork and resting on the small-diameter portion 34 of the compound roller. A back-guide 37 is provided immediately behind the smaller portion 34 of the compound roller 33. The jet unit 13, which is similar to that of FIGURES 1 and 2 is disposed pointing vertically upwards immediately in front of the compound roller 33, and a bafile plate 38 is disposed horizontally above the jet unit 13. The yarn 8 supplied is fed to the nip between the large portion 35 of the compound roller 33 and the supply roller 32. It then passes upwards round the large portion 35 and through the nip a second time and thence horizontally to the inlet 25 of the jet unit 13. Emerging upwards from the outlet 27 of the jet unit, the yarn is directed towards the baffle plate 38 but is drawn off from the neighbourhood thereof into the nip between the smaller portion 34 of the compound roller 33 and the cork-surfaced presser roller 36. After passing through the nip the yarn passes through the back-guide 37, thence beneath and in contact with the smaller portion 34 of the compound roller 33 and over and in contact with the supply roller 32 by which it is supplied to the balloon guide of the ring-spinning unit.

In the form of apparatus shown in FIGURE 4 the continuous filament bundle 8 is drawn over-end from a package 41 mounted on a rapidly rotating spindle 42, and through a balloon guide 43 by means of a set of supply rollers 44 by which the bundle is forwarded at a constant speed to the jet 13. Emerging from the jet 13 the product 15 is directed against the plate 38 and is drawn upwards round the curved edge 45 of the plate by the rotation of a collecting package or cheese 46. The cheese 46 is rotated by surface contact with a driving roller 47 at a constant peripheral speed lower than the speed of the supply rollers 44, On its way from the plate 38 to the cheese 46 the product passes through a light disc-tension device 48 and traverse guide 49.

The rotation of the spindle 42 and package 41 twist together the filaments of the bundle 8 before they reach the jet 13 but the turbulent air flow within the jet opens out the filaments as well as whipping them about to a degree sufiicient to fracture the filaments individually at intervals along their lengths. The product 15 emerging from the jet and leaving the plate 38 is thus already twisted and is collected by the cheese 46 without further twist. In order to encourage fracture of the filaments the interior of the jet 13 may be provided with an abrasive annulus as shown at 31 in FIGURE 2. Alternatively or in addition, for the same purpose,'the baffle plate 38 may have a roughened surface, particularly at the curved edge 45 where the product 15 is drawn in contact with the plate.

Instead of twisting the bundle 8 by the rotation of the spindle 42, the spindle may be held stationary and the bundle, as carried on the package 41, may be a pretwisted bundle. This enables the process to be carried out at a much higher linear rate since the linear speed of the bundle 8 does not need to be related to the revolutions of the package 41 in order to give the requisite degree of twist.

In the form of apparatus shown in FIGURE 5, a number of continuous filament yarns 8 are drawn over-end from a number of packages 51 by means of a pair of feed rollers 50 and are taken forward by the tractive effect of the air jet 13 to which they are supplied. The packages 51 may be supplied as complete packages designed for the purpose, or the yarns 8 may consist of waste yarn left on the packages after their use in another textile operation. In either case, when a package 51 is completely exhausted, it can be replaced by hand and the end of the yarn from the fresh package simply held up to the rollers 50, when it will be taken in with the remaining yarn 8 into the jet 13.

On leaving the jet 13 and the baffle plate 38 against which it is directed, the product 15 is supplied to a set of feed rollers 52 by which the product is firmly gripped and by which it is forwarded at a speed lower than that of the rollers 50 to a pair of rollers 53 which are driven with a peripheral speed in excess of that of the feed rollers 52 so as to draft the product 15. Since the breakage of the individual filaments by the action of the jet 13 is randomly distributed along the length of each filament, there may be a proportion of filament lengths substantially exceeding the distance between the feed rollers 52 and the drafting rollers 53. In this case, the drafting rollers not only draft the product 15 and reduce its total denier but also break into smaller lengths any such excessive lengths of filament. From the drafting rollers 53 the drafted product 54 is supplied to the balloon guide 55 of a ring spinning device 56 by means of which a product is twisted and collected on a package 57 as a yarn or roving.

FIGURES 6 and 7 are diagrammatic representations of two types of yarn that can be produced in accordance with the present invention. The type shown in FIGURE 6 exhibits on its surface an abundance of arch-like loops 58, a few ring-like loops 59 and a number of fibre ends 61, where the filaments have been individually broken. Most of the fibre ends in the yarn are not exhibited on the surface but are concealed within the body of the yarn. In FIGURE 7, the yarn exhibits a greater abundance of ring-like loops 59, and relatively few arch-like loops 58, but is again characterised by a number of protruding fibre ends 61 as in FIGURE 6.

The following are given as examples of how the invention may be carried out.

Example I A 60 filament cellulose acetate yarn of a total denier of 150 is supplied to the apparatus shown in FIGURE 1, or that in FIGURE 3, at 24 yards per minute, and drawn off at 22.5 yards per minute. Air is supplied to the jet unit at 30 lb. per square inch, and the ring-spinning unit is driven at 4000 r.p.m. The resulting yarn has a denier of about 170 and a twist of 5 turns per inch. The individual filaments exhibit loops, mostly arch-like in form, projecting from the body of the yarn, and also projecting fibre ends giving it the appearance as well as the full handle and other properties of a staple fibre yarn.

Example II A continuous filament cellulose acetate yarn having 52 filaments and of a total denier of 300 with about 0.5 turn per inch of twist is supplied to the feed roller 7 of FIG- URE l which is driven at 17.5 yards per minute. The draw-0E rollers 17 are driven at 12 yards per minute and air at 25 lb. per square inch is supplied to the jet unit. The ring-spinning unit is driven at 4320 revolutions per minute to give a twist of 10 turns per inch. The resulting yarn has a denier of 400; the individual filaments thereof exhibit both arch-like and ring-like curls distributed at random along their length and are broken at frequent intervals along the length of the resulting yarn so that the broken ends protrude to give the yarn the appearance and characteristics of a staple fibre yarn. The action 'of twist imparted by the ring-spinning unit binds in the broken ends as well as securing the loops and curls formed in the individual filaments.

Example III A bundle of continuous filaments of polyhexarnethylene adipamide (nylon 66) having 68 filaments and a total denier of with about 0.5 turn per inch of twist is drawn, as in FIGURE 4, from a bobbin driven at 11,000 r.p.m. The supply rollers 44 are driven at 36 yards per minute and the drive roller 47 at about 30 yards per minute. The pressure of the air supply to the jet 13 is 40 lb. per square inch. The resulting yarn is a yarn of staple fibre character having a denier of and a twist of 10 turns per inch and exhibiting both a few ring-like and an abundance of arch-like loops and protruding fibre ends.

Example IV A continuous filament yarn of 300 denier consisting of 60 filaments of polyaminocaproic acid and having 7.5 turns per inch of twist is drawn over-end from a stationary package 41 in the manner shown in FIGURE 4. The supply rollers 44 are driven at 250 yards per minute and the drive roller 47 at 200 yards per minute. The jet 13 is supplied with air at a pressure of 60 lb. per square inch. The resulting product has a denier of about 373, with 9 turns per inch of twist and exhibits some arch-like loops and an abundance of ring-like loops and protruding fibre ends.

Example V A bundle of 20 ends of continuous filament yarn of cellulose acetate, each end having 52 filaments, a denier of 300 and 5 turns per inch of twist, are drawn over-end from a number of bobbins as in FIGURE 5 and delivered to a jet to which air is supplied at 45 lb. per square inch pressure. The feed rollers 50 are driven at 6.5 yards per minute, the rollers 52 at 5 yards per minute, and the drafting rollers 53 at 25 yards per minute giving a draft of five times. The product is collected on a ring spindle driven at 2,000 r.p.m. as a roving of about 1200 denier having 0.5 turn per inch of twist.

Having described our invention, what we desire to secure by Letters Patent is:

1. Apparatus for converting a bundle of continuous filaments into a staple fibre product, said apparatus comprising a jet member having a through passage for a continuous filament bundle, means for supplying fluid under pressure to the interior of said jet member to form a turbulent fluid stream therein, the interior of said jet mem ber being formed with abrasive surfaces adapted to be engaged by the filaments under the influence of said turbulent stream, and means for drawing away and collecting as a textile product the filaments emerging from said jet.

2. A method of producing from continuous filaments yarn having the appearance and properties of staple fibre yarn, said method comprising passing a continuous filament bundle through a turbulent stream of fluid having a degree of turbulence sufficient to whip about and break the individual filaments at intervals along their lengths, passing said fluid stream and filaments through a narrow passage, drawing the resulting product out of said turbulent stream at a speed lower than that at which said filaments are fed to it, drafting said product at a speed greater than that at which said filaments enter said turbulent stream, and collecting said product.

3. A method of producing from continuous filaments yarn having the appearance and properties of staple fibre yarn, said method comprising passing a continuous filament bundle through a turbulent stream of fluid having a degree of turbulence sufiicient to whip about and break the individual filaments at intervals along their lengths, passing said fluid stream and filaments through a passage having a roughened interior surface to encourage breakage of the individual filaments, drawing the resulting product out of said turbulent stream at a speed lower than that at which said filaments are fed to it, drafting said product at a speed greater than that at which said filaments enter said turbulent stream, and collecting said product.

8 4. Apparatus for converting a bundle of continuous filaments into a staple fibre product, said apparatus comprising a jet member having a through passage for a continuous filament bundle, means for supplying fluid under pressure to the interior of said jet member to form a turbulent fluid stream therein, the interior of said jet memher being formed with abrasive surfaces adapted to be ened by the filaments under the influence of said turbulent stream, means for drawing away as a staple product the filamentary material emerging from said jet, means for drafting said staple product, and means for collecting said staple product as a staple yarn.

References Cited in the file of this patent UNITED STATES PATENTS 2,697,034 Meerdink Oct. 26, 1937 2,173,621 Campolunghi Sept. 19, 1939 2,407,109 Smith Sept. 3, 1946 2,781,555 MacHenry Feb. 19, 1957 2,825,118 Sousslotf et a1. Mar. 4, 1958 2,869,967 Breen Jan. 20, 1959 FOREIGN PATENTS 161,076 Australia Feb. 10, 1955 512,496 Canada May 3, 1955 1,100,529 France Apr. 6, 1955 

